Online tables and calculators for SPC/SQC

SQC Online offers easy-to-use calculators for various popular quality control procedures, based on ISO and other widely used standards.

Acceptance Sampling: Accept or Reject Batches

Acceptance sampling is used by industries worldwide for assuring the quality of incoming and outgoing goods. Acceptance sampling plans determine the sample size and criteria for accepting or rejecting a batch based on the quality of a sample, using statistical principles.

Many organizations require the use of ISO standards (or their ANSI/ASQC/BS/Military Standards or other counterparts) for purposes of certification. Below are online versions of Military Standard Tables (equivalent to the civilian ISO/ANSI/ASQC/BS standards), which greatly simplify the process of determining sampling plans. You can find out how many items to sample and inspect, and how to decide whether the entire batch should be accepted or rejected.

Control Charts: Is Your Process Out of Control?

A control chart is a popular statistical tool for monitoring the quality of goods and services, and for detecting when the process goes "out of control" as early as possible. Samples from the process are taken every time interval, and their quality measured. Control charts are used to track the sample quality over time and detect any unusual behavior. Below are calculators that help you to easily obtain the control chart limits for different types of measurements.

Learn about Run-Related Distributions

Many procedures in industry are based on the concept of a "run". A run is a sequence of identical events, such as a sequence of winnings in a slot machine. Many such procedures are based on rules of thumb, rather than on theory. Below is a calculator based on innovative theory developed in this field. The application shows what you should expect if applying a run-based procedure.

How long until you see the next run? Find the waiting time distribution for a specified run, given a sequence of independent success/failure events with the same probability of success ("IID bernouli trials")